code: def test_gather_sparse():
      st = random_sparse((5, 5), 15)
      dense = tf.sparse.to_dense(st)
      indices = np.array([1, 3, 4], dtype=np.int64)
      for axis in (0, 1):
          actual, _ = ops.gather_sparse(st, indices, axis=axis)
          actual = tf.sparse.to_dense(actual).numpy()
          expected = tf.gather(dense, indices, axis=axis).numpy()
          np.testing.assert_equal(actual, expected)
  
imports: import numpy
  import scipy.sparse
  import tensorflow
  from spektral.data.utils import to_disjoint
  from spektral.layers import ops
  from spektral.utils import convolution
  from spektral.utils.sparse import sp_batch_to_sp_tensor, sp_matrix_to_sp_tensor
label_desc: Use image node_id 21 for calling a global function with example usage: test_gather_sparse() without return types